Automatic service control system with fault recording



Feb. 10, 1959 s. D. VIGREN ETAL 2,873,322

' AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Filed Dec. 28. 195

19 Sheets-Sheet 1 mSEm JTTORNEYS Feb. 10, 1959 s. D. VIGREN ET AL 2,873,322

AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Q Filed Dec. 28. 1954 19 Sheets-Sheet 2 INVENTORS 52w flymaWazaW ATTORNEYS Feb. 10, 1959 Filed Dec. 28. 1954 5. D. VIGREN ETAL AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING 19 Sheets-Sheet 3 R/5 R/i RI? R18 R/S R20 192/ R22 INVENTORS jmv flaw/a Kate ATTORNEYS Feb. 10, 1959 -s. D. VIGREN ET AL 7 AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Filed Dec. 28, 1954 19 Sheets-Sheet 4 28"4 2 1 2616 27-4 H 4 2 2 F57 7 7 a L 500 500 U0 U 2 A500 ,q 1 T1 1 H956, CR3 R/ R2 R3 INVENTORS 522w flzwez l/mm/ fii izw 6/45 4%560/ ATTORNEYS Feb. 10, 1959 s. D. VIGREN ET AL 2,873,322

AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Filed Dec. 28. 1954 19 Sheets-Sheet 6 INVENTORS 510v lam? %;?0V

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AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDINd Filed Dec. 28. 1954 19 Sheets-Sheet 7 VIC 3771! 57712 57/73 ST/74- 7 INVENTORS ATTORNEYS Feb. 10, 1959 s. D. VIGREN ET AL 2,873,322

AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Filed Dec. 28. 1954 19 Sheets-Sheet 8 R2? P/l R/Z R/3 19/4 R/5 RIG /?/7 RIB R/9 R20 R2! INVENTORS 45,54 fl4/V/fl azfizzr 6/15 @5560 ATTORNEY 5 Feb. 10, 1959 s. D. VIGREN ET AL 2,873,322

AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Filed Dec. 28. 1954 19 Sheets-Sheet 9 H99 RV R2 R5 R4 R5 R6 R7 R8 INVENTORS 5)? dew/n %*mv 54 /4?! 6/45 64:55am

ATTORNEYS Feb. 10, 1959 s. D. VIGREN ET AL 7 AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Filed Dec. 28, 1954 19 Sheets-Sheet 10 5/3/72 BRM/ 1 6K /%&W 5245 @655 am ATTORNEY5 Feb. 10, 1959 s. D. VIGREN ET AL 2,873,322

AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Filed Dec. 28. 1954 l9 Sheets-Sheet ll F/lg.

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Feb. 10, 1959 s. D. VIGREN ET AL 2,873,322

AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Filed Dec. 28. 1954 19 Sheets-Sheet 13 Feb. 10, 1959 s. D. VIGREN ET AL 2, 7

AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING &

Q s a N) INVENTORS ATTORNEYS s. D. VIGREN ET AL 2,873,322

19 Sheets-Sheet 15 A I h AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Feb. 10, 1959 Filed Dec. 28. 1954 Feb. 10, 1959 s. D. VIGREN ET AL 2,873,322

AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Filed Dec. 28, 1954 19 Sheets-Sheet l6 ATTORNEYS Feb. 10, 1959 s. D. VIGREN ET AL 7 AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Filed Dec. 28, 1954 19 Sheets-Sheet 1'7 BY Q MWW ATTORNEYS v Feb. 10, 1959 s. D. VIGREN ET AL 2,873,322

AUTOMATIC SERVICE CONTROL SYSTEM wxTH FAULT RECORDING Filed Dec. 28. 1954 l9 Sheets-Sheet 18 QM MQ Feb; 10, 1959 s. D. VIGREN ET AL 2,873,322

AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Filed Dec. 28, 1954 19 Sheets-Sheet 19 LL 2 W I V0 RE/ INVENTOR5 579v flaw/c2 M686A/ 5/ %& 5/4: 445550 BY ff AUTOMATIC SERVICE CONTROL SYSTEM WITH FAULT RECORDING Sten Daniel Vigren, Stockholm, and Per Harry Elias Claesson, Danderyd, Sweden In manual telephone systems it is the task of the operators not only to set'upconnections between the subscribers but also to report arising faults to the service personnel, and then the operator also reports the nature of the fault, which highly facilitates the location of the fault.

In automatic telephone systems conditions are different. In such systems the subscriber does not as a rule report a fault 'but repeats his attempt to establish. a con.- nection. Furthermore it may oftenoccur that a faulty connection has already been released before the fault has been reported and the service stafihas had time tointervene, since nearly all switching elements in an auto matic telephone system must be designed to take down incomplete connections after a short time so that rapidly spreading congestions do not arise.

Hitherto substantially the same service organization has been used for remedying faults in manual and auto matic telephone systems. proved more and more difiicult to handle the maintenance of the latter system by fault reports and rapid fault loca: tion. However, attempts have been made to introduce in automatic telephone systems special maintenance equipment capable of responding as quickly and versatile,

1y as the automatic switching equipment. Thus for in stance so called station testers have been installed which perform repeated attempts to connectto predetermined numbers in the same manner as if, a subscriber or operator. should establish successively a large number of connections. In this way an alarm is obtained if the connection is not extended to the predetermined number.

Systematic testing of telephone exchanges, so called routine testing, has also been previously applied. In cross- United States Patent 7 2,873,322 Patented Feb. o, 1959 switching members, e. g. registers, or to connecting lines or on the whole to one or more points in a communication circuit at the moment when the respective member or part of a communication path is seized, and to record lastingly the switching or current functions taking place in the member or communication circuit respectively in the case of faults or other conditions indicating that it is desirable to make a record of information on the connection which record can be analyzed afterwards. The system is thus designed to find out whether these switching and/or current functions are normal inwhich case the indications made by the supervisory system, i. e. storage ofthe information in question, are simply cancelled, or abnormal in which case the indications are recorded be fore the supervisory system is released.

The invention thus affords the possibility of indicating exhaustive information on any connection within e. g. a telephone system, and even the route of the connection within the system can be indicated and if required, recorded in order to make it possible to locatethe fault with sufficient accuracy. The recording can take place either at the same time as the connection is established or at a later occasion.

In this way indication of information on one connection and communication circuit after the other can be obtained, while recording is performed only when desired, i. e. preferably only in the case of faults. It will be obvious that hereby all unnecessary recording can be avoided. By this arrangement the service personnel only has to give attention to such recordings whichare of importance for the localization and remedying of the fault.

By and by it has, however,

bar switching systems working according to the by-path principle another expedient for the maintenance has been created in the so called centralographs which consist of recording instruments recording within the actual exchange which elements have been used in a connection not completed and in certain cases also how far the connection has been extended. 7

Thus the known arrangements have only been capable of indicatingthe location of certain faults within the own exchange, and therefore the need of centrally operating systems for recording faults within whole automatized areas is very large. In this case the recording of, faults in the own exchange as well as faults in all the other exchanges along the connecting circuit must take place simultaneously or substantially simultaneously.

The invention described in the following affords a technically simple and economically advantageous solution of the said supervisory and maintenance problems. The invention which is applicable to telephone and tele graph systems as well as to other telecommunication systems operating wholly or in part automatically, is foremost characterized by the fact that a supervisory system is provided at a telephone exchange or at several exchanges within a larger or smaller area, said supervisory system being designed to be connected at random or in The invention is especially advantageous in automatic telephone systems, since the indicating equipment can indicate the digits dialled by a subscriber and how the registers in the telephone system send forward these digits and other control signals in the connection. Preferably there should then be included in the indicating and recording equipment a so called speech recording apparatus and a centrograph, printing telegraph receiver or similar apparatus which records the said characteristics by printing characters or numerals or punching holes or in some similar manner. Preferably the system is also combined with a finder device whichfinds out at or within which exchange a faulty connection has been stopped and eventually also in which part of such exchange the fault has occurred. This can bebrought about in different ways. Thus each exchange may be provided with a code signal sending. device which permits the identification of the exchange, or a selective network may be provided comk stopped, can be indicated by a finding procedure.

. Assuming that the indicating and recording equipment is located in a so called tandem exchange and preferably associated with the registers at this exchange, finding and recording of a connecting path from said exchange can a predetermined manner at the moment of seizure to i t be effected towards the called subscriber (the B-subscriber) as well as towards the calling subscriber (the A-subscriber). When the finding procedure is directed towards the calling subscriber, it is of coursepresupposed that the call has reached the register but'that some fault, e. g. distorted dial pulses, noise etc. has been indicated. i

Since the system may further be adapted to indicate of these characteristics. In order to reduce the number of such recordings, a certain percentage of them may be selected by means of a selecting device added to the in- 

